There has always been confusion over hitch receiver ratings as it pertains to tow vehicle ratings. This confusion applies to both motorhomes towing a dinghy and vehicles towing trailers. For example, when I was selling RVs many years ago, I had a customer who just bought a brand new truck and came to the dealership to purchase a travel trailer. He and his wife found the perfect trailer on the sales lot and wanted some pricing information. When I researched the truck’s tow capacity I informed them the truck was not rated to tow the weight of the trailer they selected. The customer told me that was impossible because the truck salesperson showed him a label that stated the truck could tow 10,000 pounds. He proceeded to take me out to his truck and pointed at the label on the hitch receiver that read 10,000 pounds. I explained, the 10,000 pounds on the label identifies what the hitch receiver is rated at, but the truck itself was only rated to tow 6,000 pounds. It was a very expensive lesson on finding the RV you want to purchase before you purchase the tow vehicle.
On a separate occasion I had a customer who wanted to tow a medium size pick-up behind a used motorhome he planned to purchase. When I told him the truck weighed too much, he argued the motorhome could easily tow 5,000 pounds. I explained that the motorhome might be rated to tow the weight of the truck, but the hitch receiver was only rated to tow 3,500 pounds. On some RVs, when frame rail extensions were added to extend the length of a chassis to accommodate the box size, it jeopardized the towing capacity. To solve the issue RV manufacturer’s installed hitch receivers with a lower weight rating to limit the amount of weight the owner would tow behind the RV.
I think you get the point, but the confusion over hitch receiver ratings and tow ratings doesn’t stop here. I have talked to many other people who translate the label on the hitch receiver to say if you use a weight distributing hitch the vehicle can tow more weight. For starters hitch receivers are rated by class. What this means is, some hitch receivers are designed for light duty towing applications and others are designed for heavy duty towing applications. Every component in a towing system has a weight rating, and the overall towing capacity is based on the weakest link in the towing chain. This applies to the tow vehicle (engine, transmission, axle ratio, cooling system, brakes and tires) and the hitch components used (receiver, ball mount, hitch ball, safety chains and weight distributing hitch components). The hitch receiver and all other components in the towing chain should be rated to tow the maximum amount of weight the tow vehicle itself is rated to tow, but if it the receiver is rated for a higher amount of weight it does not increase the tow vehicle vehicle’s maximum capacity.
Hitch receiver weight ratings are based on “maximum trailer weight” and “maximum tongue weight” the receiver is rated for. Class I and II hitch receivers are designed for light duty applications and have a 1 1/4″ receiver tube opening. Class III, IV & V hitch receivers are designed for heavy duty applications and have 2″ receiver tube openings. Note: There are extra-heavy duty and commercial-duty hitch receivers too, with 2 1/2″ receiver tube openings designed for extra-heavy duty towing applications.
Class III, IV & V hitch receivers have two weight ratings, one if it is used as a Weight Carrying (WC) hitch, and another as a Weight Distributing (WD) hitch. A WC hitch means all of the trailer’s tongue weight is supported by the hitch itself, which accounts for the lower weight capacity the hitch receiver is rated at. When you add weight distributing components (spring bars) to the equation the trailer’s tongue weight is distributed to the axles on the tow vehicle and axles on the trailer, resulting in a higher weight capacity for the hitch receiver itself. But always keep in mind, this higher hitch receiver weight rating has nothing to do with what the vehicle is rated to tow. It simply means if you use a WD hitch the hitch receiver is rated for more weight because all of the tongue weight is not resting on the hitch/receiver itself. Another important point to keep in mind is, the hitch receiver must be installed properly for the weight ratings to be accurate.
For more information on safely and properly towing a trailer, check out our RV 101 Trailer Towing Basics Video Training Program
Happy & Safe Camping,
Mark Polk
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Mark Polk
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